In the past I have ripped some old CDs which have a pre-gap of 32 frames before the first track. Ripped as tracks, and the pre-gap was left out (And can't verify the rip anymore against AR).

I found out that making a sum of this gap, extracted from any CD that has this gap, plus the "rest" of the rip in the form of image, will give me the exact full image ripped, that had those samples discarded from the initial rip.

But I also found that this can work with any other CD that has the same 32 frames pre-gap, using the same gap file. And the same goes for other gaps such as 33 frames. To the point that I can recreate old rips in its "full entirety" to be checked against AccurateRip without having to rerip all over again.

The question is rather subjective, but are these pre-gaps all binary identical by convention or will they differ as in data sound depending on the "rare" CD with that....?